Foghorn Therapeutics is a clinical-stage biotech developing small molecule drugs that target the chromatin regulatory system — the biological machinery that controls gene expression in cells. Foghorn's core thesis is that mutations in the chromatin regulatory system create dependencies that cancer cells rely on to survive, and those dependencies can be exploited to kill cancer cells while sparing healthy tissue. Foghorn's lead program, FHD-909, is an oral inhibitor of SMARCA2, a protein that certain lung cancer cells become dependent on when the related protein SMARCA4 is mutated. FHD-909 entered Phase 1 trials in October 2024, targeting non-small cell lung cancer, and is being developed in partnership with Eli Lilly. Beyond FHD-909, Foghorn has a broader pipeline of enzymatic inhibitors and protein degraders targeting SMARCA2, CBP, EP300, and ARID1B, all using synthetic lethal strategies. Foghorn has no approved products and no product revenue; the company is funded primarily through its collaboration with Lilly, which included a $300M upfront payment and an $80M equity investment when signed in 2021, plus up to ~$1.3B in potential milestones. Lilly leads clinical development and manufacturing, while Foghorn retains co-commercialization rights in the U.S. Foghorn relies on contract manufacturers for all drug production. Longer term, Foghorn aims to file up to four additional INDs, expand its proprietary pipeline, and potentially extend its platform beyond oncology into immunology and neurology.